Automatic closure for collapsible tubes



Oct. '1, 1935. L. GRUBER AUTOMATIC CLOSURE FOR COLLAPSIBLE TUBES Filed May 16, 1954 Gruber vezzfor L W4 43 A'r-r Patented Oct. 1, 1935 PATENT OFFICE AUTOMATIC CLOSURE FOR COLLAPSIBLE TUBES Ludwig Gruber, Zurich, Switzerland 1 Application May 16, 1934, Serial No. 725,907

In Germany July 17, 1933 7 Claims. (Cl. 221-60) It has already frequently been proposed to provide collapsible tubes with automatic closure devices instead of with the screw closures which are generally used; that is to say, to provide them with closure devices which open when pressure is exerted on the contents of the tube and close again when the pressure is relaxed. The automatic closure devices which have hitherto been proposed have not, however, come into practical use, for example, because they necessitated a construction of tube which differed from the usual construction and generally either could not be easily manufactured or did not function reliably or allowed the contents of the tube to become contaminated. In particular, all closure devices for collapsible tubes in which the springs which are in any case necessary for effecting the closure are liable to come into contact with the contents of the tube have proved to be unsuitable.

The object of the present invention, therefore, is to provide an automatic closure device for collapsible tubes which obviates all the disadvantages of the automatic closure devices hitherto known and does not increase the difiiculty of manufacture of the tubes to any appreciable extent and is itself not too expensive to manufacture. Since the manufacture must take place on mass production lines, any considerableincrease in manufacturing cost is out of the question.

The closure device in accordance with the invention belongs to the type of automatic closure device in which a closure member which is held in the closed position by means of a spring has a central opening at its upper end which surrounds a stationary central pin or plug.

The automatic closure device in accordance with the invention differs from the known closure devices of this kind in that both the central fixed pin or plug of the closure device and also the wall of a cap which surrounds the closure device and is firmly attached to the tube in any suitable manner. The central pin or plug of the automatic closure device may either form part of the tube itself, in which case the neck of the tube is suitably formed for this purpose or the complete closure device may be so constructed that, when assembled and finished, it can be fixed to the neck of a tube of ordinary construction by screwing 5 or pressing it on or in any other suitable manner. In this case the central fixed pin or plug of the closure device forms a separate part and is provided with a lower thickened end by which it is rigidly fixed in the outer cap of the closure 10 device, and the cap itself extends downwardly beyond the central pin and its lower end, which may be provided with an internal thread, is employed for fixing the closure device to the of the collapsible tube. 1

The closure device in accordance with the invention has the advantage that the collapsible tube itself may in any case be of the usual construction, since the neck of the tube need not be provided with any annular extensions or the like. Further, the closing spring is located in the interior of the closuredevice in a position in which it is well protected from the access of material in the tube, since the lower extension of the closure member forms a sleeve which surrounds the corresponding extension of the central pin or plug, so that this sleeve acts like a labyrinth packing. A particular advantage of an automatic closure device in accordance with the invention is,finally, that the external appearance of the tube remains substantially the same as hitherto; that is to say, the fitting of the automatic closure device does not detract from the appearance of the tube in any way and the external dimensions of the tube are the same as previously for a tube of the same capacity.

The new closure device has the further advantage that the tube can easily be manipulated in the ordinary manner, since only a weak spring closure member may be covered with cord, so that 45 V the contents of the tube are then protected from contact'with the atmosphere by a triple closure. Owing to its simple construction the closure device may be made of any suitable metal and, in particular, the displaceable closure member can be made of non-oxidizing or semi-precious metals or coated with such metal, in order to avoid any reaction with the contents of the tube, whichmight occur, for exampleyif the tubes contained substances which are to be used for neck r 1:

. both of the central fixed pin or plug and alsoof medical or pharmaceutical purposes and have the upper narrower part of the central fixed pin or plug of the closure device is of conical shape and the part of the closure member which extends upwardly from the annular shoulder has a conical bore of corresponding size, so that when the closure member is in the closed position its upper part is in contact with the central pin and forms a tight closure around it. Thus, when the closure device is constructed in this .manner,

, the closure surface is of considerable area and the tightness of the closure is thereby ensured. 'It has also been found that the upper step the closure member which surrounds the pin can be greatly reduced in size. By this means the costs of manufacture of the closure device are considerably lessened. In this case the closing spring can no'longer be arranged above the annular horizontal step of the closure member, but it is arranged outside the lower tubular portion of the closure member in such a manner that it abuts on the one hand against a support pro.-

vided at the bottom of this tubular portion and on the other hand against the inner surface of V the top of the cap which surrounds the closure and member and is fixed to the tube.

Various constructional embodiments of closure devices for collapsible tubes in accordance with the invention are illustrated byway of example in the accompanying drawing, in 'which:--

Figure 1 illustrates in cross section a form of closure device, which is complete in itself, fitted on a tube of ordinary construction having a threaded neck, the device being shown in the closed condition;

Figure 2 is a cross section on the line IIII of Figure l;

' Figure 3 me section similar to Figure 1 but with the closure device open;

7 Figure 4 illustrates in a similar view a modified form of construction of the closure device in which a portion of the closure device forms a.

part of the tube itself;

Figure 5 is a modified form of construction of the device according to Figure 4;

Figure 6 is a further modification in which the upper part of the central pin or plug is conical;

Figure '7 is a cross-section similar to Figure 6 showing the closure device open;

Figure 8 illustrates in cross section a modified form of construction of a closure device similar to Figure 6 and shows the device open.

Referring to the drawing, in all figures the tube itself is designated by the numeral I. In the form of construction of the closure device which is illustrated in Figures 1 to 3 the tube l is pro vided with the usual threaded neck 2. This neck 2, instead of being, used for fitting the; usual screw cap, is employed for fitting the automatic closure device illustrated in Figures 1 to 3. This closure device is provided with a central pin or plug of step-like shape, i. e. it is shaped like a differential piston, which is composed of the upper narrower solid pin-like part 3 and the lower hollow tubular part 4. In the annular surface which connects the two parts 3 and 4 of the Gen 5 tral plug of the closure device are arranged the two crescent shaped passage openings 5, 5. Instead of these openings a number of holes may alsobe employed. The lower thickened end 6 of the central plug 3, 4 is externally threaded and 10 is screwed into the cap 1 which is internally threaded at its lower end. The closure member 8, 9 which is also. stepped, surrounds the pin or plug 3, 4*and in its closing position its annular horizontal part II] covers the openings 5 for the 15 passage of the material contained in the tube. The tubular part 9 closely embraces the part 4 of the plug while an annular passage is left free; between the tubular part 8 of the closure mem her and the part 3 of the central pin or plug. 20 The upper end of the part 3 of the pin is slightly bevelled'or pointed and the end face of the closure member 8, 9 abuts against this end of the pin 3. This face I! contains a central opening l2; A helical spring l3 which is arranged 25 between the front end of the closure cap I and the annular surface It! tends to hold the closure member 8-, 9' permanently'in' the closed "position illustrated in; Figure 1'. The entire device is. screwed on the neck 2 of the tube 1 by means 30; of the lower end of the closure cap 1 whichextends beyond the part 6 of the central pin.

When the closure device is closed, the material in the tube fills the internal space in the hollow part 4 of the pin or plug, but it cannot pene- 35,

trate any further outwards, since. the part 3 of the central plug is solid. Owing to the relatively great length of the extension 9'of the closure f member, the material M in the tube cannot pass into the interior of the closure cap I and thus come into contact with the spring I3..

If, when the parts are in the position illustrated in Figure 1, pressure is exerted on the contents of the tube l, the closure member 8, 9, as

shown in Figure 3, israised against the action Figure 3, the end 6 of the central plug or pin .3, 4 is not screwed into the closure cap 1 but is l pressed into it. When the closure device is constructed inthismanner care must be taken that V the central pin is firmly connected to the closure can 1. V l V 0 The form of constructionillustrated in Figure 4 'differs from that which has just been described in that the central pin or plug 3Z4 itself forms a part, namely the neck, of the tube I. The lower end 6' of this pin 3, 4' is provided, in this form of construction, with an external thread on which the closure cap I is screwed. Otherwise the construction and method of operation of the closure device is the same as that of the construction shown in Figures 1 and 2. 7O

The formof construction illustrated in Figure 5'differs from that illustrated in'Figure 4 only in 7 that the closure cap I. isshorter than theclosure cap I in Figure 4 and thep'arti of the neck of the tube or the central pin is not provided with an 75 ext'ernalthread. In this form of construction, therefore, the closure cap I is pressed, soldered or fixed in other suitable manner to the part 6".

Figure 6 illustrates a form of construction of the closure device which only differs from that illustrated in Figures 4 and 5 in that the upper end 3" of the central pin or plug 3", 4" is of conical shape and the upper tubular portion 8' of the closure member 8, 9' also has a correspondingly conical bore. In this form of construction the adjacent conical surfaces of the part 3" of. the plug and of the part 8 of the closure member consequently form the actual closure of the tube when the parts are in the position illustrated in Figure 6. a

' Figure 7 illustrates the position of the parts of a closure of the type shown in Figure 6 when the contents are being extruded from the tube and this figure shows that in this form of construction, when the closure member 8', 9' is pressed upwards, an annular passage is formed around the central part 3" of the pin or plug for the outlet of the material contained in the tube.

It is obvious that in this form of. construction also the closure cap I may be connected to the neck of the tube in any suitable manner, for example either as shown in Figure 4 or as illustrated in Figure 5.

The form of closure device in which the central pin or plug 3 is conical, as shown in Figures 6 and 7, may also be constructed in the form of a complete unit, similar to that illustrated in Figures 1-3.

Figure 8 shows a form of construction of the closure device of this kind. The closure device illustrated in Figure 8 has however the further distinctive feature as compared with the forms of construction shown in Figures 6 and 7 that the conical part 3 of the central pin or plug ends in V a cylindrical part [5. Consequently, the conical part 8 of the closure member 8, 9 is provided at the end with a part l6 having a cylindrical bore. When the closure device is in its closed position the parts 3", l5 are closely embraced by the parts 8', l6 while, when the closure is in the open position shown in Figure 8, the annular part l6 of the closure member projects beyond the central portion 8' of the plug. This form of construction of the closure device has the additional advantage that when the closure is being closed the inner surface of the annular portion l6 slides along the outer surface of the part [5 and thus pushes downwards any material from the tube which surrounds the outer surface of the part iii, the consequence of which is that when the closure device closes a tight closure is always made.

It is obvious that the closure device which is shown in Figure 8 and is constructed as a unit in itself can also be made similarly to the device shown in Figures 4 to 7, so that the central pin l5, 3", 4", 6" of the closure device forms part of the neck of the tube.

The new closure device not only has the advantage that its manufacture is simpler and cheaper but the chamber in which the spring is located is also securely protected against the possibility of material from the tube penetrating into it.

I claim:

1. An automatic closure device for collapsible tubes comprising a tubular member open at one end which is adapted to fit the mouth of the tube and closed at the other end except for one or more apertures disposed laterally of a central projection, a second tubular member engaging over and slidable on the former and closed at one end except for'an aperture which co-acts With said projection, a cap surrounding both said tubular members and provided with an aperture through which the second tubular member can pass and resilient means arranged between said cap and said slidable tubular member tending to hold the slidable member in a position in which its aperture is closed by the projection on the first tubular member.

2. An automatic closure device for collapsible tubes comprising a tubular member open at one end which is adapted to fit the mouth of the tube and closed at the other end except for one or more apertures disposed laterally of a central conical projection, a second tubular member engaging over and slidable on the former and closed at one end except for a conical aperture which co-acts with said projection, a cap surrounding both said tubular members and provided with an aperture through which the second tubular member can pass, resilient means arranged between said cap and said slidable tubular member tending to hold the slidable member in a position in which its conical aperture is closed by the conical projection on the first tubular member and means for attaching the device to a collapsible tube.

3. An automatic closure device for collapsible tubes comprising a tubular member open at one end which is adapted to fit the mouth of the tube and closed at the other end except for one or more apertures disposed laterally of a central projection, a second tubular member engaging over and slidable on the former and closed at one end except for an aperture which co-acts with said projection, a tubular cap surrounding both said tubular members and provided with an aperture through which the second tubular member can pass and attached to a lateral extension of the first-mentioned tubular member, resilient means arranged between said cap and said slidable tubular member tending to hold the slidable member in a position in which its aperture is closed by the projection on the first tubular member and means for attaching the device to a collapsible tube.

4. An automatic closure device for collapsible tubes comprising a tubular member open at one end which is adapted to fit the mouth of the tube and closed at the other end except for one or more apertures disposed laterally of a central projection, a second tubular member engaging over and slidable on the former and closed at one end except for an aperture which co-acts with said projection, a tubular cap surrounding both said tubular members and provided at one end with an aperture through which the second tubular member can pass and attached near the other end to a lateral extension of the fixed tubular member and provided at this end with an internal thread for connection to the collapsible tube, and resilient means arrangedbetween said cap and said slidable tubular member tending to hold the slidable member in a position in which its aperture is closed by the projection on the first tubular member.

5. An automatic closure device for collapsible tubes comprising a tubular member open at one end which is adapted to fit the mouth of the tube and closed at the other end except for one or more apertures disposed laterally of a central conical projection, a second tubular member engaging over and slidable on the former and closed at one end except for a conical aperture which co-acts with said projection, a tubular cap surrounding both said tubular members and provided at one end with an aperture through which, the second tubular member can pass and attached near the other end to a, lateral extension of the fixed tubular member. and

provided at this end with an internal threadf-or connection to the collapsible tube, and resilient means arranged between said cap'andtsaid' is adapted to fit the mouth of the tube and closed at the other end except for one ormore apertures disposed laterally of a projecting: conical plug on the step-like surface at this end, of

the tubular member, a tubular closure member which closely embraces and is slidable on both the formentuhular member and the conical plug and: is: provided with a step-like surface. which co-acts with. the step-like surface of. the tubular member too -open and close the apertures, a cap enclosingthe tubular member together with its plug and the" closure member and provided with an. aperture through which the end of the 010- sure member can pass, a resilient member bearing against the. step of the closure member and the end of the cap and means for attaching the closure device to a collapsible tube.

' 7..An. aut.omati'c closure device for collapsible tubes in accordance with claim 6 wherein the narrower-end of the conical plug is provided with a cylindrical extension and the end of the closure member which co-acts therewith is provided with a correspondingly cylindrical bore.

LUDWIG GRUBER. 

